As the market for laptop computers, cellular phones, electric cars, and the like expands, the demand for secondary batteries having high energy density increases. As means for obtaining such a secondary battery having high energy density, a method of using a negative electrode material having a high capacity, a method of using a positive electrode having a high potential, and the like are under development. Conventionally, many of the general lithium ion secondary batteries have a voltage of 3.5 V to 4.2 V. However, lithium ion secondary batteries that use a positive electrode with a high potential have a potential of equal to or higher than 4.5 V, and an improvement in the energy density thereof is anticipated. If a negative electrode having a higher capacity is combined with a positive electrode, the capacity of the lithium ion secondary batteries is likely to be further increased.
However, the use of a positive electrode having a high potential leads to a problem in that the battery performance deteriorates due to the decomposition of the electrolyte. As a method for preventing the decomposition of the electrolyte, for example, PTL 1 discloses a method of adding an aliphatic compound or the like having a 1-propenyloxy group to the electrolyte. PTL 2 discloses a method of adding a specific fluorinated chain-like ether to the electrolyte. PTL 2 describes that an electrolyte obtains fluidity in this way. PTL 3 discloses a non-aqueous electrolyte in which a vinylboronic acid compound represented by a specific chemical formula is contained in an electrolyte. PTL 3 describes that a non-aqueous electrolyte results in excellent discharge capacity at the time of charge and discharge at a low temperature.